In other words… it was like the situation when I was a kid, before we had doppler radar and satellite photos.
I suppose some people rely utterly on the phone alerts, but the point of a tornado watch is that one could form at any time. Granted, if you’re right under it at first touch down you’re kind of screwed (unless you’re already in your basement or other safe spot) but if it sounds like a train is coming down your street and trees are flying by most people understand that getting under cover is a good idea.
Severe thunderstorm and hail also means most people are going to already be inside.
And, on top of that - the actual footprint of a tornado is kind of small, most of them aren’t very wide. While the destruction they cause can be severe where they do, actually, touch the ground if you’re just one block over your home might be untouched. Or just have bits of other houses rain down on it (which can cause damage, too, but usually not as bad as what the tornado itself causes)
I don’t want to minimize the damage - even if people are unharmed tornadoes can cause a lot of property damage. I certainly don’t want to minimize the injuries and death, all of which are tragic.
But some cultural knowledge of tornadoes and how to take cover will help in this sort of situation. Help, I’m not implying it’s a cure-all. But I do think it’s a factor why, in areas prone to tornadoes, the death rates are in many ways surprisingly low for such a violent phenomena. Where tornadoes are less common they seem to be more deadly.
I could also mention building codes - tornado prone areas often (thought not always) have building codes that take that into account, just as hurricane prone areas might take that into account in their building codes, and earthquake prone areas take that into account. That might not keep your home intact in a direct hit, but anything that slows the collpase/disassembly will give the people inside a few more seconds to get under something, down into the basement, etc. Tornadoes don’t stay very long over a particular point, if you have enough stuff around you to avoid injury by flying debris (which is the real killer, not the wind itself) for that half minute you’ll be OK. The outer walls of your house might be gone, but you’ll survive.
The tornado was in a densely populated, urban area and severe enough to cause building collapses. Having even just a few seconds warning and knowing what to do can make a big difference in that situation.